Sprue for molding apparatus.



N0. 695,543.- A Patented Mar. l8, I902.

' C. B. DAVIS.

SPRUE FOB MOLDING APPARATUS.

(Application filed Sept. 24. 1901.)

(No Model.)

WITNESSES Atlamey TN: Mourns PETERS co. PfiOTO LlTNQ, WASNXNGTON, o. c

' UNITED STATES PATENT OFF CE.

CALVIN R. DAVIS, OF SOUTH BEND, INDIANA, ASSIGNOR TO SOUTH BEN IRON WORKS, oF'so'UTH BEND, INDIANA.

SPRlJE FOR MOLDING APPARATUS.

SPECIFICATION forming part of LettersI-atnt No. 695,543, dated March 18, 1902; I l Application 1119a September 24, 1901. Serial No. 76,395. (No model.)

To a, whom it nutty OOH/0677?.

Be it known that I, CALVIN R. DAVIS, of SouthBend, in the county of St. Joseph and State of Indiana, have invented certain new and useful Improvementsin Sprues for Molding Apparatus; and I do he'rebydeclare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same. 1 4 I My invention relates to an improvement in molding apparatus, and more particularly to an improved sprue for use with the same.-

Heretot'ore serious defects have been encountered with sprues for molding-machines. One of these defects has arisen because the sprue has been arbitrary-that is, fixed in one position in relation to the machine patterns and plates-and when it has become necessary to attach different-shaped patterns in the same machine it has been impossible to fit the same to the sprue on account of having to have too long a gate, and consequently running the molten metal too far. Often two sprue; but with a fixedsprue as it is usually used in molding-machines the metal must be poured from two sprues.

It is'the object of my invention to overcome the defects which have hitherto been met with and to provide a sprue which can be set upon a pattern-plate at any point to accommodate the pattern or patterns, using one or more sprues on each plate, as maybe requiredi V p A further object is to provide a sprue which shall be simple in construction, easy. to manipulate, and which shall be effectual in all respects in the performance of its'functions.

With these objects in view the invention consists in certain novel features of construction and combinations and arrangements of parts, as hereinafter set forth, and pointed out in the claims.

In the accompanying drawings, Figurel is a View in elevation, showing a sprueembodying my invention. Fig. 2 is a view illustrating the manner of removing the conical head at the upper end of the sprue. Fig. 3 is a view illustrating the application of my improvements to a mold, this view showing the or more castings can be poured from one positions of the parts before compression. Fig. 4 is a similar view showing the relative positions of the parts of the'sprue after compression of the sand.

A represents the pattern-plate of a mold, and B myimproved telescopic sprue, the latter comprising at its base a hollow stud 1 to enter a socket in the pattern-plate A and having screw-threads 2 to mesh with similar threads inthe wall of said socket, thus to secure said stud to the pattern-plate. The stud 1 is provided with a head 3, having a conical exterior to facilitate its withdrawal from the sand. A bar 4 is disposed within and adapted to move freely through the stud-land is provided at its lower end with an annular flange or collar 5 to engage an annular shoulder 6 inside the stud for the purpose of limiting the upward movement of said bar; The bar 4 is, made with a socket ,7, opening atthe lower end of said banand .in this socket a spiral spring 8 is seated, the lower end'of said spring having its bearing in the bottom of thesocket in thepattern-plate A, said spring tending to press the bar 4 upwardly in" a manner which. will be hereinafter explained. The upper end of the bar 4 is contracted to form an annular shoulder 9 and a conical projection 10, the latter entering a socket 1 1 inthe lower-end of a removable head 12, which rests upon the annular shoulder 9 of the bar and, in effect, forms a continuation of the outer wall thereof. The removable head is made conical inform, having its wall concave and tapering from its larger upper end to its smaller lower end,

where it has a diameterexactly equal'to that of the bar4, so as to form, in effect, acontinuation of the latter, as above scated. The top face of the head is made with a recess 13, having'its end walls undercut, as shown at 14,'for the reception of the ends of a spring-bail 15, by means of which the head 12 canbe lifted off 'the bar 4 and removed from the mold.

The sprue having been secured to the pattern-plate, as above explained,- so that the parts will assume the relativepositions shown in Figs. 1 and 3, and the gate 20 placed in position, the pattern-platewillbe placed in the said box 15*, and the flask 16 will be placed in position, as shown in Fig; 3. It will be observed that the top of the head 12 comes ICO flush with the top of the flask. The flask is filled with sand loosely and struck off level with the top of flask, when the top surface of head 12 will be exposed. The sand-box is then placed under the top plate 17 of a molding-machine, when the press-plate 18 of the machine will be made to rise and press the pattern and pattern-plate against the sand and compress the same in the flask. Now it will be seen that the head 12 of the sprue and top side of the flask come in contact with the under surface of the upper plate 17 of the machine, and as the lower plate of the machine has a compression of one and one-fourth inches, more or less, the spring8 in the box 4 allows the sprue to contract in length to conform to the amount of compression of the press. When the press-plate of the machine recedes from the pressed mold, the sprue expands to its original length, the head 12 always remaining liush with the top of the flask and mold. Then the sand-box and mold are moved out from under the machine plate, when the operator inserts the bail or clip 15 into head 12 and removes the same from the mold. Then the flask is removed from the sand-box and a perfectly clean sprue-hole will be formed in the mold.

Various slight changes might be made in the details of construction of my invention without departing from the spirit thereof or limiting its scope, and hence I do not wish to limit myself to the precise details herein set forth.

Having fully described my invention, what Iclaim as new, and desire to secure by Letters Patent, is

1. In a sprue-pattern the combination with a bar adapted to yield longitudinally under pressure and a seat or support for said bar, of a head loosely seated on one end of said bar, substantially as set forth.

2. Inasprue-pattern, the combination with a bar adapted to yield longitudinally under pressure and a seat or support for said bar, of an inverted conical head, loosely resting on one end of the bar, the base of the head being of greater diameter than the end of the bar on which the head is seated.

3. In a sprue-pattern the combination with a stud, a bar movably mounted therein and a spring within the stud and supporting the bar, of an inverted conical head loosely resting on the free end of said bar.

4. In a sprue-pattern, the combination with a tubular stud adapted to be secured to the pattern-plate of a mold, of a bar carried by said stud and adapted to yield longitudinally under pressure, and a head loosely seated on said bar.

5. In a sprue-pattern, the combination with a tubular stud adapted to be secured to the pattern-plate of a mold, of a bar carried by said stud, and movable longitudinally therein, a spring for yieldingly supporting said bar and a head loosely seated on the free end of the bar.

6. In a sprue-pattern, the combination with a tubular stud adapted to be secured to the pattern-plate of a mold and an annular shoulder Within said stud, of a bar movable longitudinally through said stud and provided with a collar or shoulder to engage the shoulder within the stud.

7. In a sprue-pattcrn, the combination with a tubular stud provided at its upper end with a conical head, of a bar movable through said stud and a removable head on the upper end of said bar.

S. In a sprue-pattern, the combination of a tubular stud, a conical head at the upper end of said stud, a bar movable longitudinally through said stud, a spring under said bar,

.and a conical head removably disposed upon said bar:

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

CALVIN R. DAVIS. Witnesses:

THOMAS A. FREEMAN, FRANK W. ADAMS. 

